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The distribution, prevalence and incidence of Phomopsis vexans in six major brinjal growing agro-climatic zones of southwest India is reported. P. vexans was isolated from diseased leaf and fruit samples from six zones and was studied for its morpho-cultural and molecular characteristics. Eighteen isolates were tested for their pathogenicity on 30-days old brinjal seedlings. The ITS regions of these fungal isolates were used for the molecular identification followed by phylogenetic analysis. The incidence of leaf blight and fruit rot disease was high in northern transition zone (NTZ: 10.625.3% and 2133.3%) followed by southern dry zone (SDZ: 8.318% and 22.362%) and central dry zone (CDZ: 1017% and 2939%). All the isolates exhibited similarities in colony morphology. Variation was observed with regard to number of pycnidia, colony growth and type. Among the 24 isolates, 18 belonged to G-type and the rest could not be ascertained to either colony type. The 18 G-type isolates produced leaf blight and fruit rot symptoms 2528 and 4555 days post inoculation, respectively. In the phylogenetic analysis, all the 24 isolates formed a single clade, thus confirming their close genetic relatedness, though they were isolated from different agroclimatic zones of southwest India. Phylogenetic analysis of complete ITS2 sequence showed the presence of two distinct groups based on substitutions and indels observed among the populations where six isolates from NDZ and CDZ formed a distinct group from the rest of the isolates.

rinjal is an important vegetable crop grown worldwide. A field survey conducted during 2012 in Kerala state of South India, the little leaf disease affected brinjal plant was observed in one of the home gardens located at Nemmara (Palakkad district). The diseased and healthy samples were collected; genomic DNA was isolated and 16SrRNA gene amplified by performing nested PCR using universal primers pairs P1/P7 and R16F2n/R2 respectively. The association of Phytoplasma was detected in all the three symptomatic brinjal samples and in Phytoplasma affected Periwinkle used as positive control. An expected amplicon size of 1250bp from nested PCR was purified and sequenced. The nucleotide sequence analysis (nBLAST) of 1250bp fragment of sequence KL-50(KP027530) revealed 97% similarity with Candidatus phytoplasma trifolii (JX104336). Phylogenetic analysis and study of virtual RFLP gel pattern of the sequence also revealed the association of Candidatus phytoplasma trifolii.

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